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1.
Example-based super-resolution   总被引:38,自引:0,他引:38  
We call methods for achieving high-resolution enlargements of pixel-based images super-resolution algorithms. Many applications in graphics or image processing could benefit from such resolution independence, including image-based rendering (IBR), texture mapping, enlarging consumer photographs, and converting NTSC video content to high-definition television. We built on another training-based super-resolution algorithm and developed a faster and simpler algorithm for one-pass super-resolution. Our algorithm requires only a nearest-neighbor search in the training set for a vector derived from each patch of local image data. This one-pass super-resolution algorithm is a step toward achieving resolution independence in image-based representations. We don't expect perfect resolution independence-even the polygon representation doesn't have that-but increasing the resolution independence of pixel-based representations is an important task for IBR  相似文献   

2.
A major concern in model-driven engineering is how to ensure the quality of the model-transformation mechanisms. One validation method that is commonly used is model transformation testing. When using this method, two important issues need to be addressed: the efficient generation/selection of test cases and the definition of oracle functions that assess the validity of the transformed models. This work is concerned with the latter. We propose a novel oracle function for model transformation testing that relies on the premise that the more a transformation deviates from well-known good transformation examples, the more likely it is erroneous. More precisely, the proposed oracle function compares target test cases with a base of examples that contains good quality transformation traces, and then assigns a risk level to them accordingly. Our approach takes inspiration from the biological metaphor of immune systems, where pathogens are identified by their difference with normal body cells. A significant feature of the approach is that one no longer needs to define an expected model for each test case. Furthermore, the detected faulty candidates are ordered by degree of risk, which helps the tester inspect the results. The validation results on a transformation mechanism used by an industrial partner confirm the effectiveness of our approach.  相似文献   

3.
Ozsoyoglu  G. Wang  H. 《Computer》1993,26(5):25-38
Several user-friendly graphical database query languages that let users formulate a query by specifying a graphically aided example on the screen are compared. One of the earliest such languages, M.M. Zloof's (1977) Query-by-Example, is described. Other languages discussed are Aggregates-by-Example, Summary-Table-by-Example, and Query-by-Statistical-Relational-Table for statistical and scientific databases; Time-by-Example for historical databases; Generalized-Query-by-Example for relational, network, and hierarchical databases; Office-by-Example, Formanager, the Natural Forms Query Language, and System-for-Business-Automation for office environments; and Picquery and Query-by-Pictorial-Example for pictorial (image) databases. The basic features, query specification and interpretation, object manipulation, query language constructs, and query processing techniques used in each of the languages are discussed  相似文献   

4.
一种基于实例的汉英机器翻译策略   总被引:3,自引:0,他引:3  
介绍了一种基于实例的汉英机器翻译策略,重点讨论了汉英双语语料库的设计和基于该语料库的汉语句子的匹配算法。在进行汉语句子的匹配时,根据汉语的特点直接采用汉字的匹配,而没有进行汉语句子的分词。另外,匹配时确定匹配片断的边界也是基于实例机器翻译的难点之一,在这方面也采取了相应的解决方法。没有对翻译句子的连接装配进行更深入的研究,这是因为该翻译策略是用于多翻译引擎系统的,它要与其它翻译策略配合使用,以提高翻译结果的正确率。基于实例的机器翻译需要大量的双语语料库作为翻译时的依据,而人工建设大型语料库费时费力,所以尝试采用计算机进行汉英双语语料库的自动建立,包括篇章对齐和单词级的对齐。  相似文献   

5.
基于实例的机器翻译处理方法   总被引:11,自引:0,他引:11  
杨宪泽 《计算机工程》2003,29(21):51-52,135
在机器翻译的研究中,基于实例是一种很好的方法。文章讨论了完全实例的机器翻译、实例句型转换的机器翻译以及实例近似机器翻译。  相似文献   

6.
基于示例学习的图像人脸检测技术   总被引:4,自引:1,他引:3  
描述了一种基于示例学习的方法来检测具有复杂背景的图像中正面人脸的位置。这项技术使用了图像模型聚类的方式构造了人脸模式的分布。针对每一个图像 ,计算图像局部分布与基于分布的模板之间的特征矢量差异。然后基于这个差异 ,应用一个经过训练的分类器来判断图像当前位置是否有人脸存在  相似文献   

7.
Contrast enhancement is a very important problem in image processing. The key issue is how to assign correct enhancement levels for the local regions in an image, which makes previous methods incur much artifacts, e.g., over-enhancement, halo. In this paper, an example-based contrast enhancement algorithm is proposed, which works in the gradient domain. We utilize GMM model to describe the gradient distribution of an image. Then a GMM-based gradient mapping method is proposed to transfer the gradient of a reference image to the source image. The enhanced image is obtained by solving a Poisson equation defined by the altered gradient. Experimental results show the effectiveness and robustness of our method.  相似文献   

8.
Caricature is a popular artistic media widely used for effective communications. The fascination of caricature lies in its expressive depiction of a person’s prominent features, which is usually realized through the so-called exaggeration technique. This paper proposes a new example-based automatic caricature generation system supporting the exaggeration of both the shape of facial components and the spatial relationships among the components. Given the photograph of a face, the system automatically computes the feature vectors representing the shape of facial components as well as the spatial relationship among the components. Those features are exaggerated and then used to search the learning database for the corresponding caricature components and for arranging the retrieved components to create the caricature. Experimental results show that our system can generate the caricatures of the example style capturing the prominent features of the subjects.  相似文献   

9.
Example-based painting guided by color features   总被引:1,自引:0,他引:1  
In this paper, by analyzing and learning the color features of the reference painting with a novel set of measures, an example-based approach is developed to transfer some key color features from the template to the source image. First, color features of a given template painting is analyzed in terms of hue distribution and the overall color tone. These features are then extracted and learned by the algorithm through an optimization scheme. Next, to ensure the spatial coherence of the final result, a segmentation based post processing is performed. Finally, a new color blending model, which avoids the dependence of edge detection and adjustment of inconvenient tune parameters, is developed to provide a flexible control for the accuracy of painting. Experimental results show that the new example-based painting system can produce paintings with specific color features of the template, and it can also be applied to changing color themes of art pieces, designing color styles of paintings/real images, and specific color harmonization.  相似文献   

10.
Review Article: Example-based Machine Translation   总被引:8,自引:0,他引:8  
In the last ten years there has been a significant amount ofresearch in Machine Translation within a ``new' paradigm ofempirical approaches, often labelled collectively as``Example-based' approaches. The first manifestation of thisapproach caused some surprise and hostility among observers moreused to different ways of working, but the techniques were quicklyadopted and adapted by many researchers, often creating hybridsystems. This paper reviews the various research efforts withinthis paradigm reported to date, and attempts a categorisation ofdifferent manifestations of the general approach.  相似文献   

11.
Example-based object detection in images by components   总被引:27,自引:0,他引:27  
We present a general example-based framework for detecting objects in static images by components. The technique is demonstrated by developing a system that locates people in cluttered scenes. The system is structured with four distinct example-based detectors that are trained to separately find the four components of the human body: the head, legs, left arm, and right arm. After ensuring that these components are present in the proper geometric configuration, a second example-based classifier combines the results of the component detectors to classify a pattern as either a “person” or a “nonperson.” We call this type of hierarchical architecture, in which learning occurs at multiple stages, an adaptive combination of classifiers (ACC). We present results that show that this system performs significantly better than a similar full-body person detector. This suggests that the improvement in performance is due to the component-based approach and the ACC data classification architecture. The algorithm is also more robust than the full-body person detection method in that it is capable of locating partially occluded views of people and people whose body parts have little contrast with the background  相似文献   

12.
We introduce a novel method for synthesizing dance motions that follow the emotions and contents of a piece of music. Our method employs a learning-based approach to model the music to motion mapping relationship embodied in example dance motions along with those motions' accompanying background music. A key step in our method is to train a music to motion matching quality rating function through learning the music to motion mapping relationship exhibited in synchronized music and dance motion data, which were captured from professional human dance performance. To generate an optimal sequence of dance motion segments to match with a piece of music, we introduce a constraint-based dynamic programming procedure. This procedure considers both music to motion matching quality and visual smoothness of a resultant dance motion sequence. We also introduce a two-way evaluation strategy, coupled with a GPU-based implementation, through which we can execute the dynamic programming process in parallel, resulting in significant speedup. To evaluate the effectiveness of our method, we quantitatively compare the dance motions synthesized by our method with motion synthesis results by several peer methods using the motions captured from professional human dancers' performance as the gold standard. We also conducted several medium-scale user studies to explore how perceptually our dance motion synthesis method can outperform existing methods in synthesizing dance motions to match with a piece of music. These user studies produced very positive results on our music-driven dance motion synthesis experiments for several Asian dance genres, confirming the advantages of our method.  相似文献   

13.
An Example-based Procedural System for Element Arrangement   总被引:2,自引:0,他引:2  
We present a method for synthesizing two dimensional (2D) element arrangements from an example. The main idea is to combine texture synthesis techniques based‐on a local neighborhood comparison and procedural modeling systems based‐on local growth. Given a user‐specified reference pattern, our system analyzes neigh‐borhood information of each element by constructing connectivity. Our synthesis process starts with a single seed and progressively places elements one by one by searching a reference element which has local features that are the most similar to the target place of the synthesized pattern. To support creative design activities, we introduce three types of interaction for controlling global features of the resulting pattern, namely a spray tool, a flow field tool, and a boundary tool. We also introduce a global optimization process that helps to avoid local error concentrations. We illustrate the feasibility of our method by creating several types of 2D patterns.  相似文献   

14.
A novel method for procedurally modelling large, complex three?Cdimensional scenes is presented. Our approach is general-purpose and takes as input any three?Cdimensional model intuitively provided by a user. The algorithm exploits the adjacency between shapes and objects in the input model and computes an output model that extracts these features (constraints and adjacencies) and models the input. There are two important differences between our method and existing general-purpose model synthesis algorithms. The first is the use of a distribution for the surface or terrain on which the new model is placed. The second difference is that we automatically generate example-inherent constraints to assist the adjacency-based construction using constructive geometric constraint solving.  相似文献   

15.
汉英机器翻译中基于实例的歧义结构消解   总被引:1,自引:0,他引:1  
歧义是自然语言特别是汉语的显著特点和普遍现象,也是当前汉英机器翻译系统的主要处理难点之一。通过对其中一些常见汉语歧义结构的分析,提出一种基于实例的歧义结构消解方法。由于歧义结构的对应实例具有较高的“结构”上的代表性,通过与这些实例的相似性比较可以较准确地把握待消歧语段的内部结构。  相似文献   

16.
Example-based learning for view-based human face detection   总被引:34,自引:0,他引:34  
We present an example-based learning approach for locating vertical frontal views of human faces in complex scenes. The technique models the distribution of human face patterns by means of a few view-based “face” and “nonface” model clusters. At each image location, a difference feature vector is computed between the local image pattern and the distribution-based model. A trained classifier determines, based on the difference feature vector measurements, whether or not a human face exists at the current image location. We show empirically that the distance metric we adopt for computing difference feature vectors, and the “nonface” clusters we include in our distribution-based model, are both critical for the success of our system  相似文献   

17.
Particle swarm optimization (PSO) is a heuristic optimization technique based on swarm intelligence that is inspired by the behavior of bird flocking. The canonical PSO has the disadvantage of premature convergence. Several improved PSO versions do well in keeping the diversity of the particles during the searching process, but at the expense of rapid convergence. This paper proposes an example-based learning PSO (ELPSO) to overcome these shortcomings by keeping a balance between swarm diversity and convergence speed. Inspired by a social phenomenon that multiple good examples can guide a crowd towards making progress, ELPSO uses an example set of multiple global best particles to update the positions of the particles. In this study, the particles of the example set were selected from the best particles and updated by the better particles in the first-in-first-out order in each iteration. The particles in the example set are different, and are usually of high quality in terms of the target optimization function. ELPSO has better diversity and convergence speed than single-gbest and non-gbest PSO algorithms, which is proved by mathematical and numerical results. Finally, computational experiments on benchmark problems show that ELPSO outperforms all of the tested PSO algorithms in terms of both solution quality and convergence time.  相似文献   

18.
In the last decade the dominant models of MT have been data-driven or corpus-based. Of the two main trends, statistical machine translation and example-based machine translation (EBMT), the latter is much less clearly defined. In a review of the recently published collection edited by Michael Carl and Andy Way, this essay surveys the basic processes, methods, main problems and tasks of EBMT, and attempts to provide a definition of the essence of EBMT in comparison with statistical MT and traditional rule-based MT. Recent Advances in Example-based Machine Translation. Edited by Michael Carl and Andy Way. Dordrecht: Kluwer Academic Publishers, 2003. xxxi, 482pp. (Text, Speech and Language Technology, vol. 21) ISBN: 1-4020-1400-7 (hardback), 1-4020-1401-5 (paperback).  相似文献   

19.
20.
We present a novel approach to the real-time non-photorealistic rendering of 3D models in which a single hand-drawn exemplar specifies its appearance. We employ guided patch-based synthesis to achieve high visual quality as well as temporal coherence. However, unlike previous techniques that maintain consistency in one dimension (temporal domain), in our approach, multiple dimensions are taken into account to cover all degrees of freedom given by the available space of interactions (e.g., camera rotations). To enable interactive experience, we precalculate a sparse latent representation of the entire interaction space, which allows rendering of a stylized image in real-time, even on a mobile device. To the best of our knowledge, the proposed system is the first that enables interactive example-based stylization of 3D models with full temporal coherence in predefined interaction space.  相似文献   

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